LibreOffice is the free office suite that is compatible with all Microsoft Office files. LibreOffice is installed by default in Ubuntu. In Ubuntu 12.04, the libreoffice installation is version 3.5.3, and this tutorial will show you how to install latest 3.5.4 on Ubuntu 12.04, 11.10, 11.04 and 10.04.

Method 1. This is the easiest way installing libreoffice by adding the official ppa into your repository.

Open terminal from the dash home or press Ctrl+Alt+T, run this to add the ppa:

sudo add-apt-repository ppa:libreoffice/ppa

Update and install libreoffice:

sudo apt-get update
sudo apt-get install libreoffice

The official PPA has updated the libreoffice 3.5.5rc2 for 12.04, so Ubuntu 12.04 can use manual way installing 3.5.4 stable

Method 2. Download and Manually install Latest LibreOffice from the official site.